1. Field of the Invention
The present invention relates to apparatuses that acquire specimen images for virtual slides.
This application is based on Japanese Patent Application No. 2008-300680, the content of which is incorporated herein by reference.
2. Description of Related Art
In a conventionally employed method of specimen observation by a pathologist, etc., using an optical microscope, for example, a site in need of diagnosis is searched for by moving a stage (or a specimen on the stage) while observing the entire image of the specimen using a low-magnification objective lens, having a magnification of ×10 and an NA of about 0.4 or a magnification of ×20 and an NA of about 0.7 to 0.8; subsequently, detailed observation is conducted by magnifying the site by switching to a high-magnification objective lens having a magnification of ×40 and an NA of about 0.85 to 0.95.
However, in order to observe the site in need of diagnosis, the stage (or the specimen on the stage) is moved every time, and objective lenses are switched to change or to magnify the observation viewing field, thereby making operation tediously complicated. In addition, when sites needing diagnosis are dispersed in multiple locations in a specimen, it is difficult to ascertain relative positions at individual sites with respect to the entire region of the specimen, thus requiring considerable effort in confirming a pathological change.
In addition, if a pathologist were to, using an optical microscope, divide a specimen into a plurality of finely-divided sections, capture magnified images of individual sections, and then, paste those images together, in order to ascertain positions of individual sites with respect to the entire region of a specimen, enormous time and effort would be required, and consequently, a large number of diagnoses cannot be carried out, and a patient awaiting results of diagnosis may even suffer undesirable effects.
In addition, while a lack of doctors, etc. is becoming an issue, there are many mid- and small-sized hospitals, medical facilities in remote locations, etc. without a pathologist. Furthermore, there are particular/special and rare pathological changes whose diagnosis is difficult unless done by a pathologist who specializes in the field. In such cases, a specimen on a slide glass needs to be shipped in order to request diagnosis by a pathologist, and thus, acquiring diagnosis results requires several days.
Meanwhile, in recent years, a virtual slide production system has been proposed, which enables virtual microscope observation by capturing and accumulating specimens on slide glasses as high-resolution digital images and by displaying the accumulated digital images of the specimens on a display device such as a computer, etc. at various magnifications and observation positions.
In general, a virtual slide production system is configured to have a microscope provided with an illumination optical system, an image capturing device, and a stage that holds a specimen and that is movable in predetermined directions; a control device that performs overall control, including operating control of the above-mentioned components; and a storage device that stores digital images captured by the image capturing device. The control device finely divides an observation region of the specimen on the slide glass into fine-scale regions in accordance with the magnification, causes the image capturing device to capture images of the finely-divided regions by successively scanning the regions while moving the stage, and causes the storage device to store the images while adding positional information of the captured individual regions relative to the entire image region. In addition, in individual regions, images focused at each predetermined depth of the specimen are captured. In this way, with a virtual slide production system, three-dimensional images of regions of a specimen are captured at each predetermined magnification and are stored as digital images.
The digital images generated by the virtual slide production system can be displayed, via a virtual slide displaying system, on a display screen of a networked computer of a pathologist, showing a desired observation site at a desired magnification.
Accordingly, with a virtual slide system, in addition to not requiring tediously complicated operations as in the conventional pathological diagnosis using an optical microscope, it is possible to simplify the operation of confirming pathological changes and to shorten the time required therefor. Furthermore, because virtual slides are digital data, the digital image data of specimens can be immediately sent to a pathologist even from a remote location, and therefore, it is possible to quickly obtain diagnosis results from the pathologist.
Additionally, digital images of specimens can be shared. Accordingly, it is possible to have a plurality of pathologists simultaneously perform observation and diagnosis of the same specimen. Also, by using virtual slides as learning materials, etc. for medical students, time and effort required for individually producing slide glass specimens can be reduced and learning materials can also be standardized.
Additionally, by using virtual slides, pathological diagnosis results can be explained to a patent while displaying images of specimens on a display device.
Meanwhile, conventionally known virtual slide apparatuses in which specimen images are automatically acquired from a plurality of samples (slide glasses) via a slide loader include, for example, those disclosed in Japanese Unexamined Patent Application, Publication No. 2006-292999, Japanese Unexamined Patent Application, Publication No. 2003-248176, Japanese Translation of PCT International Application, Publication No. 2001-519944, and Non-patent Document, “Virtual Slide System, Microscope Remote Observation System, MIRAX Family”, Product Catalog of Carl Zeiss Microimaging GmbH.
In these apparatuses, a slide glass specimen (or a slide glass specimen loaded in a slide holder) is selected from a slide glass tray and is set on a stage via a slide loader, and the stage is moved to a predetermined image capturing position. Alternatively, a slide glass specimen (or a slide glass specimen loaded in a slide holder) is selected from a slide glass tray and is moved to a predetermined image capturing position via a stage that also functions as the slide loader. Subsequently, at the image capturing position, specimen images of individual finely-divided sections are captured via the image capturing device, for each slide glass specimen, by moving the stage in the x-y directions. By moving the stage in a predetermined direction upon completing image capturing of all sections, the slide glass specimen (or the slide glass specimen loaded in the slide holder) is returned to the same slide glass tray or stored in another slide glass tray.